Safety helmet



FIG. 1 is a front, top and right side perspective view of a safety helmet embodying my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof, the right side elevational view being a mirror image; and,

FIG. 6 is a bottom plan view thereof.

The person and helmet strap shown in broken lines in FIG. 1 are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a safety helmet, as shown and described. 